1. Field of the Invention
This invention relates to magneto-optical current sensors that utilize the Faraday effect with fiber optics and, more particularly, it pertains to such sensors compensated for temperature, degradation, and linearity.
2. Description of the Prior Art
The Faraday effect specifies that when a plane polarized beam of light passes through certain transparent substances along the lines of a strong magnetic field, the plane of polarization of the emergent light is different from that of the incident light. That effect has been employed in magneto-optical material to measure current in an electrical conductor. For that purpose a Faraday rotator current sensor is used and involves inherent temperature characteristics of the material's Verdet constant.
There are applications that require optical current sensing accuracies better than the 1/T temperature coefficient and cos.sup.2.sub.X linearity of an uncorrected Faraday sensor biased at 45.degree.. There is a need for a modified Faraday current sensor and associated electronic circuitry to provide compensation for temperature loop degradation, and linearity.